We believe that unique volatile signatures are associated with fungal outbreaks associated with production of aflatoxin. The long-term goal of the project is to demonstrate the feasibility of our innovative nano-crystalline tin oxide sensor detecting these unique Microbial Volatile Organic Compounds (MVOCs) at very low levels and differentiating between low levels of these unique organic vapors and other Volatile Organic Compounds and MVOC's. The resulting detector would be set inside a grain storage container to protect food safety. The first aim in this research is to identify a catalyst and operating condition, which allow these unique volatiles to be selectively detected in crop enclosures containing both the unique volatiles and potential identified interferants. Combinatorial chemistry methodology will be used to establish the conditions for unique volatile selectivity. Secondly, our aim is to provide baseline information, under biologically relevant conditions to substantiate the use of particular volatiles as markers of aflatoxin contamination. This will be accomplished by carrying out research on host plant-fungus interactions involved in the aflatoxin contamination process and doing volatile analysis on different fungal strains. The conductance response of the sensor is proportional to the concentration of these gases; that is, the higher the concentration of the gas, the greater the response. At the conclusion of this project, we expect to have demonstrated proof of principle for a sensor capable of selectively determining concentrations of unique mold related volatiles as low as 1 ppb in the presence of other typical crop related volatiles. Aflatoxins are toxic metabolites produced by certain molds in/on foods and feeds. The substance is so toxic that it is one of 19 contaminants-along with mercury and DDT-for which the U.S. Food and Drug Administration imposes strict tolerance levels in food, with only trace amounts allowed. Aflatoxins have been associated with various diseases, such as aflatoxicosis, in livestock, domestic animals and humans throughout the world. Aflatoxins have received greater attention than any other mycotoxins because of their demonstrated potent carcinogenic effect in susceptible laboratory animals and their acute toxicological effects in humans. The greatest threat of health hazards to humans come from long term exposures of tainted food products, either from spoilage or from consuming milk or meat from animals that have been fed contaminated feed. The USDA noted that countries that lack the means to regulate and monitor the presence of aflatoxin leave their inhabitants open to unknown poisonings that can continue over long periods of time. Throughout the world, approximately 4.5 billion persons are chronically exposed to largely uncontrolled amounts of the toxin where the toxic affect of aflatoxin on immunity and nutrition combine to negatively affect health factors. [unreadable] [unreadable] Mycotoxins are carcinogenic compounds that are products of the mold Aspergillus. They affect up to 30% of the worlds food supply and the resulting conclusion is that approximately 4.5 billion persons worldwide are chronically exposed to largely uncontrolled amounts of the toxin. No animal species including humans are immune to aflatoxin poisoning with the greatest threat of health hazards to humans coming from long-term exposure of tainted food products, either from spoilage or from consuming milk or meat from animals that have been fed contaminated feed. [unreadable] [unreadable] [unreadable]